A human body communication system that uses a human body, which is a dielectric, as a transmission medium is known. In the human body communication system, communication with a communication apparatus is established when the human body touches an electrode of the transmission apparatus, whereas communication with the communication apparatus is not established when the human body is not touching an electrode of the transmission apparatus. Patent literature (PTL) 1 and PTL 2, for example, disclose examples of a human body communication system.
PTL 1 discloses a technique to transmit a signal to a reception apparatus from a transmission apparatus provided with an electrode electrostatically coupled to a human body that is a transmission medium. PTL 2 discloses a technique for transmitting ID information and fingerprint information from a human body communication card holder through a human body to a control apparatus through a floor electrode disposed in the floor.